Not all of the items here are made from Corten steel but those that are are clearly marked. Corten steel is a superior type of steel which contains copper, phosphorus, nickel and chrome, this makes the steel ready weathered. The ‘ready’ rusty surface protects the steel against corrosion 6-8 times more than ‘standard’ rusty steel. The rust does not run down the wall.
The word Corten is derived from 'Corosion resistant high tensile steel' - think Angel of the North.
Other items here may not be pictured on this page as having a rust finish, but you can see on the product pages that there are rust alternatives.